Reactivities of exhaust aldehydes.

Experimental data on smog-forming reactivities of aldehydes were obtained in studies using a photoirradiation chamber. The aldehydes were studied both individually and in mixture typical of mixtures that appear in auto exhaust. Results showed reactivities of the aldehydes to differ greatly. As a group, the aldehydes in exhaust are judged to be as reactive as the olefin group. The aldehyde contribution to exhaust reactivity and methods for assessing such contribution are discussed.